my 18x8 +45 fits fine with NO scrubbing what soever.
Personally, if I didn't have to worry about my wife driving the car I would lower it to induce camber, run the 18x8.5 +38 and roll the guards. If you get a good guard roller they should be able to roll them without cracking the paint, and it will look hot as!! This size would not work without some camber induced to tuck in the top of the rim. Here is 18x9 +35 (sit 9mm further out) and this is how I would love my wheels to sit:

However, as I stated, having a wife that drives the car, low and wide wheels don't go together
So my tip to you, get the 18x8.5 +38, lower the car and roll the guards! 
Oh, and you'd want to run no more than a 235/40/18 - ideally a 225/40/18 which will be slightly stretched will be perfect
